Vacuum press and the like



April 27, 1937. BURST ET AL 2,078,565

VACUUM PRESS AND THE LIKE Filed NOV. 2, 1954 2 Sheets-Sheet 1 INVENTORS' EMANUEL 3 /25 r O S K 6116 .D UB5 7 fi/ fi/EME ATTORNEYfi April 27, 1937. E. DURST El AL VACUUM PRESS AND THE LIKE Filed Nov. 2, 1934 2 Shee'ts-Sheet 2 3 w .7 m/ M. w I 6 3 w/ 6 a 0 wf 9 6 6 6 a w 6 39 ngvamons M/I/VI/EL fives?" dies 7" 6 67%? c&

ATTORNEY Patented Apr. 27, 1937 UNITED STATES VACUUM PRESS AND THE LIKE Emanuel Diirst and Oskar Diirst, Liestal, and Max Thieme, Magdeburg, Germany Application November 2, 1934, Serial No. 751,188 In Germany October 30, 1933 13 Claims.

This invention relates to means for removing gases from soft plastic materials and refers more particularly to a so-called vacuum-press adapted to comminute a plastic mass and to compress it again after the removal of gases from said mass.

Various plastic soft materials, for instance, materials used for building purposes, and/or materials used for the manufacture of edible substances, such as chocolate or caramels are often subjected to a gas removing process in a vacuum press of this type. The soft plastic material is usually comminuted by being pressed through a device having the shape of a sieve and gases are removed by suction from this material. Then the comminuted material is again pressed together and carried out of the device.

It was found that it is hardly possible to provide means for carrying out a continuous process of this type in the course of which gases are continuously removed from the plastic material and the plastic material is continuously compressed after the removal of such gases. It was found that in many instances particles of the comminuted material collected in the exhaust passages provided for the gases and prevented these gases from escaping, so that a greater part of the gases remained within the material.

An object of the present invention is the provision of a continuously-operable degassing and compressing device comprising means maintaining a free passage for the liberated gases in the course of the degassing and compressing process.

The above and other objects of this invention may be realized through the provision of a device comprising means for comminuting and compressing a soft plastic material, means for removing the gases liberated from the comminuted material and means for maintaining a free passage for said gases while the material is being compressed.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings showing preferred embodiments of the inventive idea.

In the drawings:

Figure 1 shows in section a horizontal vacuum press.

Figure 2 is a section along the line 2-2 of Figure 1, looking in the direction of the arrows.

Figure 3 shows in section a comminuting compressing and degassing device of the vertical type.

Figure 4 shows in section another device of the combined horizontal and vertical type.

Figures 5, 6, 7 and 8 show different means for maintaining a free passage for the liberated gases.

The device shown in Figs. 1 and 2 of the drawings comprises a transporting screw H) which is firmly mounted upon a shaft I One end of the shaft II is provided with a pulley |2 driven by a belt I3 which may be operated by any suitable motor not shown in the drawings. The shaft II is supported by a bearing l4 of the cover of a casing l5, which forms a cylindrical chamber I8 surrounding the screw Ill and which is provided with an opening l6 formed by the converging walls of a spill I1.

The plastic material is inserted into the chamber l8 through the opening l6 and is transported through this chamber by the screw 0.

A wall l9 provided with openings 20, separates the chamber l3 from a chamber 2| formed by the casings 22 and 23 and by the nozzle 24. The casing 23 which is connected by screws 25 with the casing 22 and by the screws 26 with the nozzle 24, comprises a bearing 21 supporting one end of the shaft I and rigidly connected with the casing 23.

The plastic material transported by the screw l0 through the chamber I8 is pressed by the screw l0 through the openings 20 of the wall I9 and thus penetrates into the chamber 2| in a comminuted state. The comminuted material is compressed again by the screw 28 situated within the chamber 2| and rigidly mounted upon the shaft The chamber 2| forms the degassing chamber of the device. This chamber is closed at the top by the bottom 28 of a cylindrical casing 29 comprising a pipe 30 leading to a vacuum pump which is not shown in the drawings. The cylindrical casing 29 is closed by a cover 3| connected by screws 32 with the casing 29. Screws 33 are used for connecting the casing 23 with the casing 29.

The casing 23 should be connected with the nozzle 24 in an air tight manner and air tight packing should also be provided between the easing 23 and the casing 22, between the casing 23 and the casing 29, as well as between the casing 29 and the cover 3|.

When suction is created within the pipe 30, the gases freed within the chamber 2| are sucked in through an opening 34 provided in the bottom 28 of the casing 29 and in a member 35 supporting the perforated wall l9 separating the chamber l8 from the chamber 2|.

The screw 28 compresses the comminuted mass and transports it in a direction toward the nozzle 24. At the same time gases contained in this mass are removed through suction created in the pipe 36 and pass through the opening 34 and the vacuum chamber 36 formed by the casing 29 into the pipe 36. The plastic mass is pressed by the screw 29 against the nozzle 24 and is removed through the opening 31 of this nozzle.

As shown more clearly in Figure 1 of the drawings, the member 35 supporting the wall I9 has the shape of two concentric cylinders 38 and 39 interconnected by a web 46. Due to the shape of the supporting member 35 an annular chamber 4| is formed between the cylindrical walls 38 and 39. A plate or a similarly shaped member 42 is situated within the annular chamber 4| and is firmly attached to the rotary screw 28.

When the screw 28 is rotated, the member 42 will be rotated along with the screw and will remove any particles of the plastic material which can otherwise collect within the chamber 4| and clog the opening 34, thus preventing the gases from escaping into the chamber 36 within the chamber 2|. rotary member 42, the passage for the gases is kept free during the entire comminuting and compressing processes so that a continuous degassing of the comminuted substance is achieved.

It is also possible to use a vertical reciprocating piston 43 for the purpose of preventing the clogging of the opening 34. The piston 43 may be reciprocated by means of a rod 44 attached to said piston and passing through an opening formed in the cover 3|, care being taken that the adjacent surfaces of the movable and stationary parts are maintained as air tight as possible. The rod 44 is pivotally connected with the lever 45 carried by a. support 46 and driven by a rod 41 which is operated by a cam 48, carried by a shaft 49. A pulley 56 is used for driving the shaft 49 and is connected by a belt 5| with a pulley 52 firmly mounted upon the shaft II.

The vacuum chamber 36 may be provided with an opening 53 covered by glass to enable the operator to inspect the interior of the vacuum chamber 36.

Fig. 3 of the drawings illustrates a comminuting and degassing device of the vertical type, which is provided with a cylindrical casing 66 having converging upper walls 6| forming an opening 62 for the plastic material. The casing 66 is connected by screws 63 with a lower casing 64 surrounding a chamber 65. A vertical shaft 66 is situated within the chamber 65 formed by the casing 64 and the chamber 61 formed by the casing 66, and is supported by a bearing 68 connected with the casing 64. The shaft 66 is rotated by a belt 68 passing over a pulley 69 which is rigidly mounted upon the shaft 66. Another pulley 16 is firmly mounted upon the shaft 66 and is connected by a belt 1| with another pulley 12 mounted upon a shaft 13 which carries a cam 14. The cam 14 is used for reciprocating a piston 15.

The shaft 66 carries a screw 16 situated within the chamber 61 and another screw 11 situated within the chamber 65.

A wall 18 provided with openings 19 separates the chamber 61 from the chamber 65. Concentrical cylindrical walls 86 and 8| are pro vided within the chamber 65. The annular space 83 formed between the walls 86 and 8| is used for the passage of the comminuted substance from the chamber 61 into the chamber 65. The annular chamber 84 formed between Due to the provision of the the concentrical wall 8| and the adjacent wall of the casing 64 communicates through a passage 85 with a vacuum chamber 86 which is formed by a casing 81 rigidly connected with the casing 64 and with the casing 66. The casing 81 carries a pipe 88 leading to a vacuum pump which is not shown in the drawings. A plate 89 is firmly attached to the screw 11 and is rotatable along with said screw.

In operation, the comminuted substance is fed into the chamber 61 through the opening 62 and is transported through the chamber 61 by the screw 16 driven by the shaft 66 through the medium of the pulley 69. The plastic material is pressed by the screw 16 through the openings 19 of the wall 18 into the chamber 65.

At the same time vacuum is created within the pipe 88 so that the gases contained in the plastic material escape through the annular space 84, the opening 85 and the chamber 86 into the pipe 88. The passage between the vacuum chamber 86 and the chamber 65 is kept free by means of the plate 89 rotating within the annular space 84 along with the screw 11. The comminuted material is compressed by the screw 11 and is pressed through the opening 96 of the nozzle 9| which is connected by screws 92 with the casing 64. The opening 85 can be maintained open from the side of the vacuum chamber 86 by means of the piston 15 which is moved toward the opening 85 by means of the piston 15 which is moved toward the opening 85 by the cam 14 and is then returned to its original position by means of the coil spring 93. The separating wall 18 situated between the chamber 61 and the chamber 65 is carried by a disc shaped support 94 which is rigidly connected with or forms an integral part of the cylindrical walls 86 and 8|.

The device illustrated in Fig. 4 of the drawings is a combination of the vacuum press of the horizontal and vertical type. The device comprises a casing I 66 provided with converging walls MI and surrounding a vertical shaft I62 carrying a. screw I63. The lower end of the shaft I62 carries a screw I64 situated within a chamber I65 formed by a casing I 66 connected by screws I61 with the casing I 66. A wall I 68 provided with perforations I 69 separates the chamber II6 formed by the casing I66 from the chamber I65 formed by the casing I66. The separating wall I68 is carried by a support H6 consisting of a pair of concentrieal cylindrical walls I and H2. An annular space 3 is formed between the walls III and H2. A vacuum chamber 4 is formed by a casing H5 and communicates with the chamber. I65 through an opening H6.

The casing I 66 is connected by screws with another casing II8 containing a horizontal screw II9 firmly mounted upon a shaft H1. The shaft I62 is driven by a pulley I 26 while the shaft H1 is driven by a pulley I2I. The rotation of the shaft I62 is transmitted to a pulley I22 connected by means of a belt I23 with a pulley I24 carried by a shaft I25. The shaft I25 drives a cam I 26 which reciprocates a piston I21 situated within the vacuum chamber II 4. The chamber I28 formed by the casing II8 terminates in a nozzle I29 provided with an opening I36.

The plastic material inserted into the chamber 6 through the spill IN, is pressed by the screw I63 through the openings I69 of the separating wall I68 into the chamber I65. At the same time the pipe I3I connected with the vacuum chamber H4 is placed under vacuum so that the gases liberated within the chamber I05 are sucked through the space H3 and the opening H6 into the vacuum chamber H4. The screw I04 transmits the comminuted plastic material to the chamber I28 wherein this material is compressed by the screw H9 and is pushed through the opening I30 of the nozzle I29.

The passage between the chamber I05 and the vacuum pipe I3I is kept free from the comminuted material through the provision of a plate I32 which is situated within the space H3 and which is rotated along with the screw I04. The opening H6 can also be prevented from being clogged by the comminuted material through the provision of a piston I21 which is reciprocated by the cam I26 and the coil spring I33.

Several devices of diiferent constructions may be provided for the purpose of cleaning the passage connecting the degassing chamber with the vacuum pipe.

The device shown in Fig. 5 of the drawings comprises a degassing chamber I40 formed by the cylindrical casing MI and connected through the medium of an opening I42 with a vacuum chamber I43. A vacuum pipe I44 is attached to the casing I45 constituting the walls of the vacuum chamber I43. The opening I42 of the vacuum chamber I43 is kept free from particles of the plastic material by a revolving scraper I46 firmly mounted upon a shaft I41, which is driven by a pulley I48. The pulley I48 is connected by a belt I49 with a pulley I50 firmly mounted upon a shaft I5I, which carries the screw used for comminuting the plastic material within the chamber I40.

The device shown in Figure 6 of the drawings comprises a casing I60 containing a screw which is mounted upon a shaft I62. A casing I63 surrounds the vacuum chamber I64 which is connected with the chamber I65 formed by the casing I60, through the medium of an opening I66 which is partly closed by a rotary roller I61. The casing I 63 carries a vacuum pipe I68. The revolving roller I61 is driven by a pulley I68 which is rotated by a belt I passing over a pulley I1I which is firmly mounted upon the shaft I62. Due to the provision of the roller I61, the plastic material is prevented from clogging the passage I66 so that gases liberated within the casing I65 will freely pass from the chamber I65 into the vacuum chamber I64 and the vacuum pipe I68.

In the modification shown in Figure 7 of the drawings the degassing chamber I80 formed by the casing I8I is in communication with the vacuum chamber I82 formed by the casing I83 by means of an opening I84, which is partly covered by rollers I85 and I86 revolving in two difierent directions. The roller I86 is driven by a belt I81 rotated by the shaft I88. The rotating rollers I85 and I86 prevent the plastic material from clogging the opening I84 so that the gases liberated within the chamber I80 can freely pass into the vacuum chamber I82.

The device shown in Figure 8 comprises a degassing chamber I90 formed by a casing I9I and connected by a passage I92 with a vacuum chamber I93 formed by a casing I94. A screw I95 mounted upon a shaft I36 is rotated within the passage I92. The purpose of this screw is to prevent the material from clogging the passage I92.

As shown in Figure 8, an air tight packing is produced through the provision of a stuffing box I91 provided with packing glands I98 which are lubricated from the containers 200.

Various changes can be made in the shown constructions without departing from the spirit of this invention, which is limited only by the appended claims.

What is claimed is:

1. A vacuum press and the like comprising a casing, a rotary screw within said casing, means forming a degassing chamber, another rotary screw within said chamber, a perforated separating wall situated between said degassing chamber and said casing, means forming a vacuum chamber, said vacuum chamber being connected by a passage with said degassing chamber, and means connected with the second mentioned screw for removing a plastic material from said passage.

A device in accordance with claim 1, comprising separate reciprocating means for maintaining said passage free from the comminuted material.

3. A vacuum press and the like comprising in combination with a preliminary compression and comminution chamben'a degassing chamber directly connected with said compression and comminution chamber and a rotary screw extending through said chambers for transporting the material to be treated from said compression and comminution chamber through said degassing chamber; means forming a separate vacuum chamber, means forming at least one passage connecting said vacuum chamber with said degassing chamber and means in said vacuum chamber for intermittently opening and closing said passage.

4. The combination with a vacuum press and the like comprising a preliminary compression and comminution chamber, a degassing chamber and a rotary screw for transporting the material to be treated through said chambers; of means forming a separate vacuum chamber, means forming at least one passage connecting said vacuum chamber with said degassing chamber, means in said vacuum chamber for intermittently opening and closing said passage and synchronized reaming means in said degassing chamber whereby comminuted material may be cleared from said passage when in closedposition.

5. A vacuum press and the like comprising in combination with a preliminary compression and comminution chamber, a degassing chamber and a rotary screw for transporting the material to be treated through said degassing chamber; means forming a separate vacuum chamber, means forming at least one passage connecting said vacuum chamber with said degassing chamber, means in said vacuum chamber for intermittently opening and closing said passage comprising at least one piston adapted to be reciprocated in said passage.

6. The combination with a vacuum press and the like comprising a preliminary compression and comminution chamber, a degassing chamber and a rotary screw for transporting the material to be treated through said chambers; of meansforming a separate vacuum chamber, means forming at least one passage connecting said vacuum chamber with said degassing chamber, means in said vacuum chamber for intermittently opening and closing said passage comprising at least one piston adapted to be reciprocated in said passage, and synchronized reaming means in said degassing chamber whereby comminuted material may be cleared from said passage when in closed position.

7. The combination with a vacuum press and the like comprising a preliminary compression 5 and comminution chamber, a degassing chamber and a rotary screw for transporting the material to be treated through said chambers; of means forming a separate vacuum chamber, means forming at least one passage connecting said vacuum chamber with said degassing chamber,

and means in said vacuum chamber for-intermittently opening and closing said passage comprising a segment-shaped scraper adapted to be rotated adjacent said passage.

8. A vacuum press and the like, comprising in combination with a preliminary compression and comminution chamber, a degassing chamber and a rotary screw for transporting the material to be treated through said degassing chamber;

means forming a separate vacuum chamber, means forming at least one passage connecting said vacuum chamber with said degassing chamber, a segment-shaped scraper, and means for rotating said segment in a circle adjacent said passage to intermittently open and close said passage.

9. A vacuum press and the like, comprising in combination with a preliminary compression and comminution chamber, a degassing chamber and a rotary screw for transporting the material to be treated through said degassing chamber; means forming a separate vacuum chamber, means forming at least one passage connecting said vacuumchamber with said degassing chamber, means in said vacuum chamber for intermittently opening and closing said passage, and movable synchronized ventilating and cleaning means in said degassing chamber, the last-mentioned means maintaining in said degassing 4o chamber an annular space which is free from the material to be treated and passing adjacent said passage when said passage is closed by the thirdmentioned means.

10. A vacuum press and the like, comprising in combination with a preliminary compression and comminution chamber, a degassing chamber and a rotary screw for transporting the material to be treated through said degassing chamber; means forming a separate vacuum chamber, means forming at least one passage connecting said vacuum chamber with said degassing chamber, means in said vacuum chamber for intermittently opening and closing said passage, the last-mentioned means comprising at least one piston adapted to be reciprocated in said passage;

and movable synchronized ventilating and cleaning means in said degassing chamber, the lastmentioned means maintaining in said degassing chamber an annular space which is free from the material to be treated and passing adjacent said pasage when said passage is closed by the thirdmentioned means.

11. A vacuum press and the like, comprising in combination with a preliminary compression and comminution chamber, a degassing chamber and a rotary screw for transporting the material to be treated through said degassing chamber; means forming a separate vacuum chamber, means forming at least one passage connecting said vacuum chamber with said degassing chamber, a segment-shaped scraper, means for rotating said segment in a circle adjacent said passage to intermittently open and close said passage, and movable synchronized ventilating and cleaning means in said degassing chamber, the last-mentioned means maintaining in said degassing chamber an annular space which is free from the material to be treated and passing adjacent said passage when said passage is closed by the third-mentioned means.

12. A vacuum press and the like, comprising in combination With a preliminary compression and comminution chamber, a degassing chamber and a rotary screw for transporting the material to be treated through said degassing chamber; means forming a separate vacuum chamber, means forming a passage connecting said vacuum chamber with said degassing chamber and a rotatable roller situated adjacent to said passage for maintaining said passage free from the material to be treated.

13. A vacuum press and the like, comprising in combination. with a preliminary compression and comminution chamber, a degassing chamber and a rotary screw for transporting the material to be treated through said degassing chamber; means forming a separate vacuum chamber, means forming a passage connecting said vacuum chamber with said degassing chamber, a plurality of rotatable rollers situated adjacent to said passage for maintaining said passage free from the material to be treated, and movable ventilating and cleaning means in said degassing chamber, the last-mentioned means maintaining in said degassing chamber an annular space which is free from the material to be treated.

EMANUEnpi'IRsT. OSKAR mms'r. MAX TI-HEME. 

